1. Field of the Invention
The present invention relates to a pneumatic radial tire suitable for use in high-performance passenger cars, and more specifically to an ultralow section radial tire.
2. Description of the Prior Art
Recently, high-performance passenger cars with a ratio of the vehicle weight to the maximum output horsepower is 8 kg/Hp or less have come into wide use with increasing highways and user's choice of superior quality cars. In pneumatic tires used for these high-performance passenger cars since a higher vehicle turning performance is required during travelling, a prior-art pneumatic tire, has the rigidity of the belt layers increased along the tire circumferential direction to reduce the deformation of the tire crown portion such has been proposed for providing a higher vehicle turning performance.
In the above-mentioned prior-art pneumatic tire, however, there still exists a problem in that the vehicle turning performance has not yet been satisfactory to such an extent as to be required for the present-day high-performance passenger cars.